Jōmon Sugi, Ancient cedar tree in Yakushima, Kagoshima Prefecture, Japan

Jōmon Sugi is a Japanese cedar tree in Yakushima in Japan that rises 25 meters tall with a trunk measuring more than 5 meters across. The crown sits above a dense forest of younger trees, and the bark is so thick it folds into deep grooves running the full height.

Scientists place the age somewhere between 2,000 and 7,000 years, though no one knows the exact date it first grew. Discovery by a forester in 1966 brought it into wider public awareness and triggered a wave of visitors to the island.

The name Jōmon Sugi refers to the Jōmon period of Japanese prehistory; one explanation says the estimated age of over 4,000 years meant the tree had lived since then, another that its wildly twisting trunk resembles Jōmon pottery. The tree was first called Ōiwa Sugi when Teiji Iwakawa, tourism chief of Yakushima Town Hall, found and publicized it in 1966. In April 2009 it was twinned with Tāne Mahuta, a kauri of about 1,200–2,500 years in Waipoua Forest, New Zealand, to foster traditional cultural and youth exchanges.

The trail leading there follows a forest path roughly 5 hours one way, so bring sturdy shoes and rain gear. The viewing deck sits about 15 meters from the trunk to protect the roots, so a camera with zoom helps capture details.

The platform went up in 1993 after studies showed thousands of visitors each year compacting the soil and damaging the root network. Since then no one is allowed closer than 15 meters to the trunk, a measure that has stabilized its growth.